Download Chapter 3 Rocks and Minerals: Mineral Building Blocks

Chapter 3 Rocks and Minerals
Lesson 1 Minerals: The Building Blocks of Rocks
Notes
Main Idea:
All rocks are made up of minerals. Minerals may be identified by their physical properties.
Vocabulary
Mineral (140) - natural, nonliving, substances that make up rocks
Luster (142) – the way light reflects off the surface of a mineral
Cleavage (142) – the way a mineral splits
Streak (143) – color of the powder left when a mineral is scratched along a white tile called a streak plate
Hardness (144) – property of a mineral that refers to its ability to scratch another mineral or be scratched by
another mineral
Mohs’ hardness scale (144) – shows the hardness of a few common minerals.
Ore (146) – rocks that are mined because they contain useful minerals.
What is a mineral?
Main idea:
Rocks are different from each other because they are made up of different kinds of minerals.
Supporting Details:
1. Minerals are natural, nonliving substances that make up rocks.
2. Some rocks (e.g. granite) are made up of several kinds of substances
3. Some rocks (e.g. marble) are made up of only one substance.
4. Each type of mineral is made up of the same element or combination of elements.
5. Each type of mineral has a certain crystal shape.
a. Some crystals are shaped like cubes.
b. Some are like hexagons
c. A crystal’s shape is based on the orderly way its atoms are arranged.
6. Scientists have identified over 3,000 kinds of minerals, of which 30 are common in rocks.
How are minerals identified?
Main idea
Minerals are identified by their physical properties such as color, luster, streak, cleavage, and hardness.
Supporting Details:
1. Minerals are identified by their many physical properties.
2. Color
a. Color alone cannot be used to identify a mineral as several minerals have the same color.
b. Other properties must be used.
3. Luster
a. Luster is the way light reflects off the surface of a mineral.
b. Some minerals have a metallic or shiny luster
c. Other minerals may be dull.
d. Some minerals may have a glassy, pearly or greasy shine to them.
4.
5.
Cleavage
a. The way a mineral splits is called its cleavage.
b. Some minerals, like mica, split along a flat surface into thin sheets.
c. Other minerals, like calcite, split along a flat surface to form a flattened- cube like shape.
d. Other minerals, like quartz, split apart unevenly.
Streak
a. Streak is the color of the powder left when a mineral is scratched along a white tile.
b. Some minerals leave a streak that is the same color as the mineral.
c. Other minerals leave a different streak color.
d. The streak is always the same for the a given mineral
How can hardness be used to identify minerals?
Main idea:
Minerals can be identified by their ability to scratch other minerals.
Supporting Details:
1. Hardness is a property that refers to a mineral’s ability to scratch another mineral or be scratched by
another mineral.
2. Mohs’ hardness scale shows the hardness of a few common minerals.
3. Any mineral can be scratched by any mineral with a equal or higher hardness number.
4. Hardness of a mineral can be also determined by using everyday items to see which scratch the mineral.
What are minerals used for?
Main Idea
Minerals are used to make everyday products.
Supporting Details:
1. Gems are rocks that are valued for their beauty. Some gems (e.g. diamonds) are also valued based on
their hardness and ability to cut.
2. Ores are rocks that are mined because they contain useful minerals.